Tektronix CMC251, Руководство пользователя

Страница: 36 / 38

Appendix B: Maintenance
26
CMC251 User Manual
Troubleshooting
Electronic maintenance on the CMC251 Frequency Counter must be
performed by a trained technician. However, an operator can perform
some basic and routine maintenance. The CMC251 Frequency
Counter will give some indications of problems to aid the operator.
WARNING.
To prevent electrical shock, unplug the power cord and
disconnect the signal input cable from any signal source before
checking or replacing the fuse.
No Display with Power On
If the digital display is not lighted, but the POWER button is pushed
in and the CMC251 Frequency Counter power cord is plugged into
an outlet, do the following steps:
1. Check the line fuse. If the fuse is open, replace it.
2. If the line fuse is good, check the power outlet for proper voltage.
If the outlet voltage is incorrect, call service personnel.
WARNING. To prevent electric shock, disconnect the power cord from
the power source and the CMC251 Frequency Counter before
checking continuity.
3. If outlet voltage is correct, check power cord continuity. If the
power cord fails the continuity check, replace the power cord.